Update free-programming-books.md

Added book to Mathematics section

Added some more books. I've found both of these extremely useful :)

Added book to Datamining section

Introduction to Statistical Thought by Michael Lavine

The Elements of Statistical Learning: Data Mining, Inference, and Prediction.  By Trevor Hastie, Robert Tibshirani, and Jerome Friedman

Added book by David MacKay to Machine Learning section

Information Theory, Inference, and Learning Algorithms

Added first line (python) in italian list

Added The wikibooks 'x86 Assembly guide'

Added "Network Security Tools" book to the Network section

Added a Drupal Framework section under php literature with a couple of f...

Added Machine Learning Books

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	free-programming-books.md

Added Programming with gtkmm and GUI category

Added subcategory for Backbone.js and a link for 'Developing Backbone.js...

Sage for Power Users by William Stein

Conflicts:
	free-programming-books.md

Conflicts:
	free-programming-books.md

add Haskell: A Gentle Introduction to Haskell

Added "Object-Oriented Reengineering Patterns" by Demeyer, Ducasse & Nie...

Added a few MOOCs